Liquid crystal display (LCD) is commonly used as a display device because of its capability of displaying images with good quality while using little power. An LCD apparatus includes an LCD panel formed with liquid crystal cells and pixel elements with each associating with a corresponding liquid crystal cell and having a liquid crystal capacitor and a storage capacitor, a thin film transistor (TFT) electrically coupled with the liquid crystal capacitor and the storage capacitor. These pixel elements are substantially arranged in the form of a matrix having a number of pixel rows and a number of pixel columns. Typically, scanning signals, generated from a gate driver, are sequentially applied to the number of pixel rows, through a plurality of scanning lines along the row direction, for sequentially turning on the pixel elements row-by-row. When a scanning signal is applied to a pixel row to turn on corresponding TFTs of the pixel elements of a pixel row, source signals of an image to be displayed, generated from a source driver, for the pixel row are simultaneously applied to the number of pixel columns, through a plurality of data lines arranged crossing over the plurality of scanning lines along the column direction, so as to charge the corresponding liquid crystal capacitor and storage capacitor of the pixel row for aligning orientations of the corresponding liquid crystal cells associated with the pixel row to control light transmittance therethrough. By repeating the procedure for all pixel rows, all pixel elements are supplied with corresponding source signals of the image signal, thereby displaying the image signal thereon.
Liquid crystal molecules have a definite orientational alignment as a result of their long, thin shapes. The orientations of liquid crystal molecules in liquid crystal cells of an LCD panel play a crucial role in the transmittance of light therethrough. It is known if a substantially high voltage is applied between the liquid crystal layer for a long period of time, the optical transmission characteristics of the liquid crystal molecules may change. This change may be permanent, causing an irreversible degradation in the display quality of the LCD panel. To prevent the LC molecules from being deteriorated, the polarity of the voltage signals applied on the LC cell has to be changed continuously. Usually, a source driver is configured to generate such voltage signals having their polarity alternated according to an inversion scheme such as frame inversion, row inversion, column inversion, or dot inversion. Typically, one or more portions of the source driver are classified into the positive and negative types. The driving voltages for the positive and negative driver circuits are the same. However, the range of operational voltage is twice larger than that of the driver circuit with the single polarity. As a consequence, the power consumption of the source driver increases substantially. Additionally, notwithstanding the inversion schemes, a higher image quality requires higher power consumption because of frequent polarity conversions. Such LCD devices, in particular thin film transistor (TFT) LCD devices, may consume significant amounts of power, which may in turn generate excessive heat. The characteristics of the LCD devices will be significantly deteriorated due to the heat generated.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.